Table 3.

Analysis of cotransfer of Knr and Smr to characterize spontaneous Smr revertants

Recipient strainDonor DNAaGrowth (CFU/ml) with selection on:Smr frequency per 100 Knr cells
R800R9742.99 × 1063.6 × 1041.20
R9894.18 × 106<10<0.0002
R10012.86 × 106<10<0.0003
R416R9747.76 × 106Rb
R9897.76 × 106Sb
R10017.76 × 106Rb
  • a DNA from Knr transformant of R800 after transformation with the indicated strain.

  • b Cells from two Knr colonies were plated in the presence or absence of 200 μg of Sm per ml to assess their resistance (R) or susceptibility (S).